1. Technical Field
The instant disclosure relates to a semiconductor packaging process, in particular, to a semiconductor package structure with double-side cooling function and the manufacturing method thereof.
2. Description of Related Art
Highly integrated and miniaturized semiconductor products are trending consumer products, and widely used in the motor controlling field. The use of brushless DC motors (BLDC) in motor electronics and medical products has increased, and the ratio in the market thereof exceeds other types of motors. Along with the increased need for BLDC and the development of the related motor techniques, the development strategy of the motor control systems has changed from independent circuit forms to power module forms.
A basic motor system is shown in FIG. 16 and comprises three main units: a power electronic element, a gate driver and a control unit. In addition to packaging the discrete power electronics such as insulated gate bipolar transistor (IGBT), fast recovery diode (FRD) and metal-oxide-semiconductor field-effect transistor (MOSFET) with other related components and temperature detecting devices for forming a module, some applications integrate the gate driver into the module. Aside from completely integrating the three-phase control in the same module, in some larger electric current applications, the units are packaged into a single phase module. The above types of power modules are for the application of high current power and high current and hence, the semiconductor devices used therein will generate a large amount of heat. Therefore, the existing module packages have insufficient heat dissipation property and need additional heat dissipation structures for effectively dissipating heat.
Although existing techniques can operate and perform effectively, some disadvantages still exist. For example, U.S. publication Nos. 20090160044 and 20130020694 disclose the techniques relating to module packaging. The conventional power module manufacturing process mainly combines die attach and wire bonding processes. Furthermore, some methods including substituting aluminum wires with aluminum ribbons or using copper materials having better conductivity and heat dissipation ability such as copper ribbons to reduce wire resistance are also presented. Since the conventional manufacturing processes involve electrically connecting the power chips in the power module by wire bonding, the heat generated by the power chips cannot be effectively dissipated.
In addition, the use of wire bonding process increases the parasitic inductance and affects the operation frequency. Besides, the electromagnetic interference (EMI) induced by the parasitic inductance is a problem which cannot be ignored. For improving the heat dissipation property, a double-side cooling technique is provided and is used in the hybrids mobiles. However, such techniques still employ die attach for assembling the components and has the disadvantage of high manufacturing complexity, low yield, insufficient testing coverage for the chip and low feature matching, thereby causing inconsistency of performance.
Discrete component electronic circuits are convenient to assemble and have the advantage of low manufacturing cost and are suitable for mass production. Therefore, most of the circuit boards are produced in this way. Power modules have the advantage of excellent reliability and heat dissipation ability. There is a need to combine the advantage of the above two types of assembling technique to achieve a power module with double-side cooling property which is easy to produce.